I'm building up a frame that I'll probably ride lots. I'm on a "retired guys" budget so mid-level components and I'm fine with that. Does anyone have a reasoned preference for 105 or Rival? Any parts I should upgrade to Force or Ultegra ( e.g. brifters, etc.)? Thanks.

Shimano=no brainer

Have 105 on a soma smoothie ES and rival on a cannondale caad, both are older 9 spd. Aside from set up differences, if I were blind folded, not sure I could tell the difference. However I think rival is a better deal, liked force brakes better than rival.

What are you used to using?

Which hoods feel better in your hand?

This!

I have Force on one bike, & don't especially like the shape of the brake hoods- kind of a big hump under your palm.

I have had them both and like them both. However I have now switch everything to SRAM including getting rid of my Dura Ace shifters. To me and me alone Shimano is smoother than either SRAM or Campy. However there seems to be more precision with SRAM and you get more feedback on what gear you selected. That and by pulling the lever to the bar it is easier to shift from the drops. May not matter to you but it did to me, I have small hands and the reach and throw are shorter on SRAM, unless you were looking at DI-2. I believe Rival can slot in between 105 and Ultegra and Apex is closer to 105. So if I like them both why did I go with SRAM? Better pricing and shorter throw because you can shorten the arc by pulling the shifter closer to the bar. Fewer accidental shifts when hitting the brakes, (for me) And it is easier if all your bikes shift the same way. They tend to be slightly lighter, or were and when I built up the Tarmac. I got a deal on SRAM Red and a Wi-Fi derailleur. I like double tap.

Whichever you like better for whatever reason you like it better. Both are fine component groups.

While I agree with what BluesDawg has written, I have Shimano on my commute bike (Ultegra) and SRAM on my club ride bike (Force) and overall (everything considered) I prefer the SRAM.

That said, it's your purchase, your bike. You try both and then decide which is best for you.

Rick / OCRR

I've always had Shimano on my bikes. Had a bike with that "double tap" crap for a short while. Never really liked it.
Another vote for Shimano.

I presume you're not trying to say that people with no brains choose Shimano. If the choice were that cut-and-dried, one of them would be discontinued by now.

I recently test rode two bikes of different sizes and same model, one Tiagra and one 105. The Tiagra shifters felt twangy, and they're ugly. The 105's definitely felt smoother and I preferred them. But also I thought I could feel the friction from the cable routing.

OP here. Yes, I've hefted both the 105 and Rival hoods. (I'm used to Campy Centaur and Veloce.) I have small hands and felt that the 105 hoods were like trying to get grip on Dolly Parton. The Rivasl were smaller but a little more comfortable and so more grippy... and seemed to have a "quicker" response time than Dolly's.

I purposely avoided Campy evangelism in my initial response. But, good Lord man, stick with Campy. I recently picked up a complete (down to cables and brakes) Centaur group from Ribble. It is amazing.

I went from SunTour (good stuff for the times except for their last attempts to rival Shimano) to Campy. But I want to keep the price in bounds AND try something new. LOL... I do recall shifting (and "overshifting") with Campy Nuovo Record....guaranteed to fail you when chased by a dog!)

I went through it recently, and the big issues for me was feel, conventional "Brifter" vs "Double Tap", and price. Felt I could get used to either, and went for price and got the 105.

Nuovo Record doesn't work so good with ultra narrow freewheels. Suntour Superbe does. I'm even going with a First Generation Cyclone for a new (old) build with a 13-24 ultra 7 freewheel. If I could get a 13-23 for under $100 anymore I would have gone with another Superbe. That's how much I liked the first one with friction shifting. I was sold on slant parallelogram derailleurs 30 years ago.

And they call me a Ludite......Ha !!

Sram vs Shimano? Tough call. I have two Sram bikes and one Shimano bike. They both really have their pluses and minuses

Sram
Easier to set up and adjust, very simple shifter mechanism takes little care, it is nice to brake aggressively and never worry about accidently shifting, can reach the shifter with ease in any position even in the drops and shift with a very short throw. Shifts sound and feel slightly clunky but never miss.

Shimano
Smoother shifting. The long throw of the shifter can be awkward at times depending on what position your are in on the bars. The shifters are complex and when they start to go they are a throw away item.

Both sets of hoods feel just fine after the first ride.

I was a big Shimano fan and disliked Sram before I owned a Sram set and adjusted to the double tap.

Bottom line, both are good but if I could only have only one type, it would be the Sram.

SunTour ratched barcons are still smoothly useful... in fact, I use them on one bike today. A strain of Ludite is useful sometimes in cutting through the hype. Given that, brifter shifting is still a huge improvement, even if not quite as "satisfying" as a smooth dt shift working j
ust when you need it.

Never heard this statement before? Shimano all the way.

SRAM has the precision feel of Campy, has a shorter throw than Shimano, and shifting is separate from brake lever. I find it easier to use and gets my vote.

However, I prefer Campagnolo because I really like the solid shift performance, the "button", and the aesthetics. The stuff makes me drool all over myself.

Rival... double tap shifters are a "no brainer".

I'm in the middle of building up a new frame. It's being built up with Shimano,